Folding apparatus

ABSTRACT

Apparatus for folding sheet material in which apparatus panels disposed in opposed relation form a receiving surface for the receipt of sheet material to be folded. The panels are provided with vacuum ports which the sheet material overlies and the production of suction pressure retains the sheet material securely on the forming board. The panels are pivotally mounted such that they are movable between a position in which the oppositely disposed panels lie in substantially planar relation and a position in which the panels are in substantially parallel relation. Tucking of sheet material transversely to provide fold lines in the material is accomplished by shaping the panels to appropriate configurations. A preferred form of the apparatus includes a plurality of the folding boards supported on a carrier permitting continuous operation. Additionally, mechanism mounted on the carrier provides for assisting tucking or folding operations.

United States Patent ['19] Spencer et al.

[ Jan. 1, 1974 1 FOLDING APPARATUS [73] Assignee: Kimberly-ClarkCorporation,

Neenah, Wis.

[22] Filed: Sept. 2, 1971 [21] Appl. No.: 177,301

Primary Examiner-Robert W. Michell Assistant Examiner-A. HeinzAttorney-Daniel J. Hanlon et a1.

[ ABSTRACT Apparatus for folding sheet material in which apparatuspanels disposed in opposed relation form a receiving surface for thereceipt of sheet material to be folded. The panels are provided withvacuum ports which the sheet material overlies and the production ofsuction pressure retains the sheet material securely on the formingboard. The panels are pivotally mounted such that they are movablebetween a position in which the oppositely disposed panels lie insubstantially planar relation and a position in which the panels are insubstantially parallel relation. Tucking of sheet material transverselyto provide fold lines in the material is accomplished by shaping thepanels to appropriate configurations. A preferred form of the apparatusincludes a plurality of the folding boards supported on a carrierpermitting continuous operation. Additionally, mechanism mounted on thecarrier provides for assisting tucking or folding operations.

8 Claims, 23 Drawing Figures PATENTEDJAH um saw OlflF 12 FIG.

PATENTED AN T I974 SHEET (120! 12 PATENTEDJAH H974 3,782,714

saw 030; 12

PATENTEBJAH 974 3.782.714

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PATENTEDJAH 1 I974 SHEET 05 0F 12 FIG.4

PATENTEUJAN 1 1914 SHEEI 070F PAIENTEUJAM 1 1914 SHEEI 08 0FIPATENTEDJAH 1 1974 SHEEI 10 0F PATENTEDJAH 11974 3.782.714

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- tailed description FOLDING APPARATUS BACKGROUND OF THE INVENTION 1.Field of the Invention This invention relates to sheet folding apparatusand more particularly concerns apparatus for the folding of disposableabsorbent articles such as diapers into contoured configurations so thatthe article conforms readily to a wearer.

2. The Invention With Relation to the Prior Art The folding of flexiblematerials, and specifically materials having a somewhat non-uniformstructure, is of increasing importance as disposable materials becomemore prominent in commerce. The folding is required to be uniform fromarticle to article to accommodate modern packaging techniques and toinsure commercial acceptability. Exemplary of articles demandingaccuracy and reproducibility in folding while yet necessarily beingfolded on a production basis are disposable diapers, particularly thosewhich are contoured to accommodate themselves to the shape of wearers,such as young children. A diaper of the kind under consideration isdisclosed in I-Irubecky U. S. Pat. No. 3,196,874.

Additionally, sheet materials of the paper tissue kind and those whichcombine tissue with nonwoven materials in the toweling, bib, napkin andlike fields are articles which require folding to desired shapes at asubstantial production rate.

It is, accordingly, a primary object of this invention to provideapparatus for the folding of sheet material which is widely applicablein the paper and similar producing industries.

An important object of the invention is to provide a novel folding boardarrangement which has particular utility as a component of apparatuswhich automatically folds sheet material at a substantial productionrate. The board provides for the folding of material lengthwise ofitself and may substantially simultaneously 'provide for the making oftransverse folds or folds angularly disposed to the length and width ofthe sheet material as desired.

A further and more specific object of the invention is to provideapparatus for folding a disposable diaper along a medially located linelengthwise of itself and to 'tuck edge portions of the diaper inwardlycentrally of the diaper length to provide a generally triangular fold inthe diaper with a centrally disposed pocket.

Other objects and advantages of the invention will be more readilyapparent by reference to the following deand accompanying drawingswherein:

FIG. 1 is a perspective view of a diaper folding apparatus incorporatinga plurality of folding boards in accordance with a preferred embodimentof the invention;

FIG. 2 is an essentially schematic view in side elevation illustratingfold positions of a diaper folding board as the board progresses in theoperation of the apparatus of FIG. 1 from the machine inlet to themachine outlet positions;

FIGS. 3 and 3a are fragmentary and sectional views which, takentogether, illustrate the mechanism for effecting folding boardoperations, the views being taken in the direction of the position ofmachine outlet;

FIG. 4 is a somewhat enlarged and fragmentary sectional view taken online 4-4 of FIG. 3;

FIG. 4a is a view like that of FIG. 4 to a somewhat smaller scaleillustrating particularly the camming mechanism for actuation of thefolding boards and associated equipment;

FIG. 5 and 5a through FIGS. 8 and 8a illustrate corresponding positionsof the diaper'folding mechanism and the fold in the diaper itself atspecific stages of the operation;

FIGS. 9 and 10 are detail views of the diaper folding mechanism;

FIG. 11 is a schematic view illustrating a mode of determining relativeshaft positions for operation of the specific folding mechanism;

FIGS. 12, 13 and 14 are detail views of a pusher mechanism for effectingdiaper removal from the folding mechanism;

FIGS. 15 and 16 are detail views illustrating an arrangement of assistfingers for effecting diaper folding with a deep centrally positioneddiaper pocket; and

FIG. 17 is a view in plan of a power source arrangement for theequipment operation described.

In broad aspect the mechanism in accordance with the invention includesa folding board which moves in a predetermined path and intercepts anarticle to be folded, such as the mentioned disposable diaper. It isapparent that other sheet material may be folded to predeterminedconfigurations in accordance with the principles of the invention andthat the diaper structure in its passage through the mechanism fullyillustrates these principles. The diapers in the preferred practice ofthe invention move to the folding board in essentially planar condition.

The folding board includes a pair of oppositely disposed panels arrangedto be pivoted from a position in which the panels form essentially aplane to receive the planar disposed diaper, to a position in which thepanels lie in substantially parallel relation with the diaper foldedlengthwise about a medial transverse fold line of the diaper. Thepanels, for the purpose of securely retaining the diaper as it isfolded, each include rearwardly disposed on the panel a housingcommunicating with vacuum ports. Accordingly, as a diaper is transferredto the folding board, a leading edge of the diaper lies across theleading end of the first panel and the application of vacuum holds it infixed position relative to the panel. As the folding board moves, thediaper is further drawn onto the second and trailing panel, and thetrailing edge of the diaper lies across and is retained by the vacuumcondition existing at the ports of the trailing end of the second panel.

The panels are suitably shaped to provide for fold lines in the diaperadditionally to the medial transverse fold line. In specific applicationthe panels are of a generally triangular configuration and of the samedimensions so that, upon folding the flexible material, the productshape is substantially symmetrical about the medial fold line. Theattainment of the additional fold lines is with the aid of tuckingelements which suitably function simultaneously with the pivotalmovement of the panels and may be actuated from machine componentscommon to the panels or from components independently actuated.

For production operations a plurality of the folding boards are providedon a carrier which traverses a closed path from a diaper inlet zone to adiaper outlet zone, returning to the inlet zone for the reception of acontinuing supply of diapers to be folded. The folding board panels aresuitably each controlled in their movement from the planar open positionto a parallel or closed folded position and return to the open positionby cam means moving in a fixed track and supported by the carrier.Additionally, a cam actuated device is provided to assist diaper removalfrom the folded or collapsed folding board.

In the specific embodiment disclosed, the carrier includes anarrangement to assist folding and provide a relatively deep pocketcentrally of the diaper. This arrangement acts in conjunction with eachforming board as it approaches the diaper outlet zone and issynchronized with the movements of the carrier and folding boards topermit entry to and withdrawal from the partially folded diapers in areciprocating action.

The diapers in their folded condition, with the folding board panelslying in generally parallel relation to each other, are relatively fixedin position even after removal of the vacuum conditions. To aid removal,each folding board includes means, suitably cam actuated, for urging thediapers from the boards while the panels are in their folded position.

Referring to the drawings more in detail, the numeral 11 in FIGS. 1 and2 indicates a diaper moving in planar arrangement in the direction ofthe arrows toward a transfer roll 13 which carries a fixed vacuum box15. The diaper 11 may be of any construction suitable to be folded inthe manner such as is, for example, generally indicated in FIG. 8a. Thediapers commony are formed of a composite of flexible materialsincluding a liquid impermeable ply as of polyethylene, an absorbent plyas of wood pulp fibers, and a soft bodycontacting ply of reinforcedtissue as is well-known in the art. Further details of construction arenot essential to the practice of this invention but a useful diaperconstruction is more specifically shown in U. S. Pat. No. 3,196,874previously mentioned herein.

A plurality of the diapers as particularly indicated in FIG. 2 move insuccession in spaced apart relation to the roll 13 and are carried tothe roll on a wire screen 17 under the influence of vacuum applied froma fixed vacuum box 19. The screenv 17 is conveniently supported onrollers in well-known manner, one roll being indicated at 21 in FIG. 2.

The folding apparatus is generally designated by the numeral 22 (FIGS. 1and 2). It includes a pair of oppositely disposed carrying plates 23,24retained in spaced relation by a plurality of horizontally extendingspacers 12 which are also hollow and serve as conduits for air flow in avacuum system later to be described. The plates 23,24 are fixedlyretained on a main shaft 25 (FIGS. 1, 2 and 3) for rotation therewith byconventional keys as at 28. Framing 26, which includes a transversemember and a pair of uprights, support the shaft 25 rotatably onbearings as indicated at 26a (FIG. 3). As shown most clearly in FIGS. 1and 2, a plurality of folding boards generally indicated at 27 areprovided and carried in rotation between the plates 23,24 for thepurpose of acting on a corresponding plurality of diapers simultaneouslyto fold them from the flat position of FIG. 1 to the position generallyindicated in FIG. 8a. The sequence of folding steps is illustrated inFIGS. a through 8a, and the corresponding folding board positions areshown in FIGS. 5 through 8.

Referring now to the movement of the folding boards 27, in the presentinstance the general type of mechanism is a cam actuated one. For thispurpose the frame 26 fixedly carries a pair of cam plates 29, one oneach side of the apparatus (FIGS. 3 and 3a). Two plates 29 are employedin practice for smooth operation. For convenience one cam plate and itsassociated equipment for rotation of the panels of a folding board, asillustrated particularly in FIG. 3, will be described in detail but itis to be understood that the operations on each side of the machine foractuation of the panel folding mechanism will be similar. Each of thefolding boards 27 is actuated in the same way by separate cam means, asmay be clearly seen from FIGS. 4 and 4a. Corresponding parts, whereconvenient, are designated by corresponding numerals. Also in FIGS. 3and 3a for sake of clarity in illustration, the panels are at to theirnormal position.

The panels 27a, 27b of a folding board are actuated through a single camon each cam plate 29. Thus, cam plate 29 receives a cam follower 30which moves in a cam track 31. The follower 30 is carried by a bellcrank 32 which has a hub 33 of rotation and carries at one end gearteeth 34 arranged as a sector of a gear. The teeth 34 mesh with atoothed gear 35 fixedly retained (FIG. 3) on an inner hollow tubularshaft 36 (FIG. 5). The shaft 36 is integral with bevelled gear 37 whichmeshes with pinion 38, the latter meshing with bevelled gear 39 forrotation with respect to shaft 36. Gear 39 is integral with outer shaft41. Bearings indicated at 40 support the gear 39 and outer shaft 41 forrotation with respect to the inner shaft 36, the concentric shafts 36and 41 having opposite rotational directions. Panel support armsdesignated at 42a and 42b are respectively secured to outer shafts 41and 36.

The panels 27a, 27b at their oppositely disposed rearward ends, as shownin FIG. 5, have housings 45 and vacuum ports 44 which communicate thehousing interiors with the atmosphere. Conduits 43 (FIGS. 3 and 3a)connect to vacuum pump means (not shown) and air flow may take placefrom the housing interiors through the second and hollow tubular arms42b and hollow shafts 36. Each housing is closed off interiorly at oneend as most clearly shown in FIG. 3 to provide for air passage from thefolding board surface to the housing interior and vacuum application tomaterial resting over the ports 44. A second support arm 42b, and afirst support 42a (which is suitably solid and blocked off from theinterior of housing 45 to provide for the vacuum effect) are connectedwith each panel for driving it in rotation as illustrated in FIGS. 5through 8. For this purpose the radial distance of the arms 42a, 42b areequal from the axial center of the hollow shaft 36 so that each armcooperates smoothly in providing for the movement.

The numeral 46 (FIGS. 1 and 3) generally designates a bracket forretention of the gear cluster 37, 39 to which reference has already beenmade. Each bracket includes a mounting plate 47 secured fixedly to acircular carrying plate for traveling in rotation with the plate. Asindicated in FIG. 3, shaft 41 is rotatably mounted with respect to andsupported by this plate 47. This permits free rotation of the outershaft 41 relative to the plate 47. The other outer oppositely disposedplate 48 of each bracket 46 is hollow, providing for air flow to theconduits 43 from the arms as already noted (FIGS. 3 and 3a).

The movement of the arms to effect panel movements is permitted by thegimbal joint arrangement, more specifically described in connection withFIGS. 9

and 10. As shown, each arm 42a and 42b fixedly carries a mount 49. Themount 49 threadedly receives a bearing screw 50 (FIG. which is itselfpivotally retained on block 51 by roller bearing 54. The pivot block 51also includes a second bearing screw 52 which is threadedly received ina mount 53 carried on the extremity of a wing or fold member 56.Provision for rotation of the bearing screw 52 is made by the rollerbearing 55 similar to bearing 54. Member 56, effect indicated at 57, ishingedly connected to a second and similar wing 58. The wings 56,58 intheir movement, as indicated in FIGS. Sthrough 8, ffect folding of thediaper as indicated in the views shown in FIGS. 5a through 8a. Morespecifically, shafts 36 and 41, driven as already indicated and whichare associated with the arms 42a, 42b, cause the arms 42a, 42b to movethrough the positions indicated in FIGS. 5 to 8. As such movement takesplace, the wings 56,58 are caused to collapse on themselves and alsoinwardly against the diaper, urging the diaper into a fold conditionsuch as is indicated, for example, at 11h and 11g in FIG. 6a.

The wings 56,58 themselves collapse inwardly upon movement of the arms42 due to the gimbal joint arrangement illustrated in FIGS. 9 and 10 andpreviously described. The lines of fold are determined by selection ofthe relative axial alignment of the axes of bearing screws 50,52 asindicated at 50 and 52 in the schematic illustration FIG. 11. (In FIG.11, for convenience, the schematically illustrated gimbal jointcomponents have the same numerals in other figures but are primed.) Morespecifically, the line GA, for example, extending from the simulateddiaper center to a diaper corner and beyond provides one axis while aline l-IA projected from the point l-I provides the second axis 52 Theseaxes lie along the intended lines of fold of the diaper and angularly tothe medial transverse foldline EF. When oriented, as shown in FIG. 11,the diaper, upon movement of the wings 56,58 as indicated, results inprimary diaper sections 11a, 11b and outer side folds 11c, 11d, 11g, and11h as well as inwardly disposed folds lle, 11f, lli, and 11j.

It will, accordingly, be understood from the foregoing that in therotation of plates 23,24 the brackets 46 and their associated plates 47rotatably secured to the hubs 33 move the followers 30 in theirrespective tracks 31 and through the mechanism previously described,causing the panels 27a, 27b of the folding boards to move through thesteps indicated in FIGS. 5 through 8. Specifically, the panels which arespaced apart lengthwise in end-to-end relation to define a gap forforming a transverse fold line in the diaper are oscillated or rotatedto a back-to-back position with the gap maintained. In the course ofthis action a diaper which has been delivered in lengthwise planardisposition to a folding board as in FIG. 2 is completely folded in thecourse of its passage from the transfer roll 13 to the removal jaws 14.Also, in the course of this action, the diaper is subjected to vacuumconditions as indicated in FIG. 2 Thus, at the first station lp vacuumis applied to the leading end of panel 27a by drawing air through thevacuum ports 44 which are positioned forwardly on the folding board 27.The air flow is to the shaft 36, conduit 43 (FIG. 3) and throughspacer-conduit 12 to the rotary valve 9 and p'ort 10 of the valve, theexhaust to vacuum being by legend indicated in. FIG. 2. The rotary valve9 is of a conventional type in which openings 8 in circular plate 23(FIG. 2) and also plate 24 are covered and uncovered sequentially inknown manner in plate rotation relative to the valve to providerespectively for stopping and starting of air flow.

In the drawing the solid lines indicate air flow from the vacuum portsto the hollow shafting. The solid lines indicate air flow or thepresence of vacuum conditions at the leading end of the foldin'g'board;the dash lines indicate the presence of vacuum conditions at therearward end of the board, and the absence of solid or dash linesindicates that vacuum conditions are not present.

Accordingly, as shown at positions 2p through 4p (FIGS. 2 and 4a), thediaper is retained in positions as the panels in their movements causefolding of the diaper longitudinally about the median transverse foldline. As the folding board traverses its path from position 4p to 5p,the vacuum condition is removed and the diaper is free to move from theports and to be withdrawn by suitable mechanism at station 5p. In thetravel to the position 6p under the influence of the cam means 30, thefolding board opens toward a substantially planar condition.

To assist the removal of the diaper at the station 5p (FIG. 2) themechanism as is particularly illustrated in FIG. 3 and more in detail inFIGS. 12 to 14 is provided in association with each folding board. Asillustrated in FIGS. 3 and 4, the frame 26 carries a cam plate forreceiving a plurality of cam followers 61 in the track 62. Each follower61 is retained by a bell crank 63 (FIG. 4). Each bell crank is providedwith a hub 64 which is received on a shaft 65. Each shaft 65 throughbearing 66 rotatably supports the bell crank from the rotatable carrierplate 24. A bearing retainer nut 67 provides for retention of a shaft 65on a bell crank 63. Each bell crank 63 carries teeth 68 which mesh withthe teeth of a gear 69 supported by a bushing 70 which itself receives akey 71 (FIG. 3). A key 71 is received by each shaft 72 so that a gear 69drives a shaft 72. Each shaft 72 is suitably supported by bearings 73 asindicated particularly in FIG. 3. As is apparent in the rotation of thecarrier plate 24, the shafts 72 are driven through the followers 61 ofbell crank 63. I

A circular plate 74 (FIG. 4) suitably termed a pusher support plate issecured for rotation with shaft 25 through key 75 (FIG. 3). The pushersupport plate 74 rotatably supports each shaft 72 of the diaper pusherassembly. Each shaft 72 carries a sector gear 76 which is retained onthe shaft by a clamp screw 76a. Each sector gear 76 meshes with anddrives a rack 77. A fixedly positioned backing roller 78 (FIG. 4)associated with each pusher assembly guides each rack in its rectilinearmovement as does a guide block 79. Each rack 77 on its extremity isprovided with a suitably shaped pusher 80 (FIGS. 4, and 12-14).

Referring now to FIGS. 12-14 inclusive, a pusher 80 of each foldingboard acts against brackets 81 which form part of the mechanism forassisting diaper removal from the diaper folding boards. Only one pusherassembly will now be described in detail. Pins 82 carried on oppositeends of a spirng 83 are retained by the forward bracket 81 and rearwardbracket 84. Further, bracket 81 is fixedly retained on a movable slide85 on the under side of each of the panels 27a,27b of the folding board.Each slide 85 carries a block 86 of nylon, the slide and block beingretained together by nut and bolt assemblies 87.

The nylon block 86 moves in a slot 88 extending in each of the panels ofthe folding boards as indicated most clearly at 27b in FIG. 12.Accordingly, when a pusher is actuated by the movement of the shaft 72under control of a cam follower 61, a diaper on the folding board willbe urged outwardly of the board and the board assumes the position ofFIG. 13. As most clearly seen from FIG. 3, the actuation of the diaperremoval device is governed by the relationship of a cam follower 61 tothat of the cam follower 30, and these are so synchronized that thediaper is urged from the plate at the proper station as indicated inFIG. 4a.

It has been found desirable to assist the action of the wings or foldingmembers 56,58 in the folding of the diapers and to achieve a relativelydeep central pocket. For this purpose there is provided the mechanismillustrated in FIGS. 15 and 16. Referring first to FIG. 15, there isindicated at a pair of fold assist tubular rods 90 through which an airflow may be directed. These rods are received on pivot blocks 91 whichinclude a base 92 and, since each rod arrangement is similar, only onewill be described in detail. The base 92 receives therethrough a screw93 (FIG. 16). A cross-arm 94 receives the screw 93 in threadedengagement and nut 95 abuts the cross-arm retaining the screw andcross-arm in fixed relation. One extremity of the screw 93 (FIG. 16)rotatably receives block 91; for this purpose the bearing 96 is providedto effect the rotational support. Each of rods 90 is thus pivotallymounted with respect to cross-arm 94.

The cross-arm 94 is slotted at 97 and receives cap screws 98 which arethreadedly secured in an extremity of bar 99. The bar 99 is providedwith stud shafts 100 (FIG. 17) which rotate within the bar, the studshafts being carried on extremities of the cranks 101. A first crank 101receives shaft 102 while the second crank 101 receives shaft 103 (FIGS.15 and 17). The bar 99 describes an essentially orbital or generallycircular motion with the centers of shafts 100 moving in an arcuatefashion about the centers of shafts 102,103.

Shafts 102 and 103 are driven in a manner more clearly seen from FIG.17. In FIG. 17 the numeral 105 designates an electric motor source ofpower. Motor shaft 106 carries pulley 107 which, through belt 108,drives pulley 109 and shaft 110. A suitable right angle drivearrangement 112 connected by couplings 111 from shaft to shaft 113provides for actuation of gear 114. Gear 114 drives main gear 115carried on main shaft 25 to which reference has already been made.Second gear 116 on shaft 113 drives gear 117 and hence shaft 118 andgear 119. The latter gear cooperates with gear 120 to drive shaft 102.Shaft 102 carries pulley 121 which drives timing belt 122 and pulley 123on the shaft 103. Thus, shafts 102 and 103 are rotatably supported byframe 26 and are arranged to rotate in timed relation. The rotation ofshafts 102,103 cause movement of the cranks 101 and hence movement ofthe arm 99 and cross-arm 94.

Cross-arm 99 provides for the movement of the fold assist rods 90 in anarcuate motion so that the rods 9 may enter the diaper in sin arcuatemotion as the diaper is being folded and as 'the diaper and the foldingboard carrying it itself move in a closed path.

For the purpose of guiding the inward and outward movement of the rods90 freely of other parts of the mechanism and the diaper itself, alinkage system controls motion of the rods 90 in a generally oscillatingmanner. More specifically, from each fixed frame support 26 a bracket130 is provided. A pair of ball joints 124 carrying a rigid link 125(FIG. 16) are respectively secured to brackets and to the base 92 of theblock 91 forfree pivotal movement. Retaining means 127 of conventionalnature such as a threaded bolt and screw effect securing to the brackets130 and with rigid arms 125 tend to limit the movements of each of thebases 92 carrying the rods 90.

The retaining means 128 serve to retain rigid arms 125 to base 92 andbase 92 is slotted to provide for adjustability and to permit accuratelocation of the retaining means.

The rods 90 are hollow for the purpose of directing air through themagainst the diaper to assist folding and also to aid release from thediaper. For this purpose air lines 126 communicate with the rods asindicated in FIG. 15.

The diapers passing from the folding boards to the jaws 14 are ready forpackaging and may be directed to suitable cartons in known manner.

Mechanism as described is capable of handling diapers of a size of about12% inches by 17% inches at a rate of up to 200 diapers per minute, andmore. The folding boards, panels having their edges which taper from therelatively wide rearward end to a narrow forward terminating at the gapbetween panels, are as described suitably on 24 inch centers about thecarrier periphery, and the carrier plates 23,24 rotate at a speed ofabout 40 rpm.

As many apparently widely different embodiments of this invention may bemade without departing from the spirit and scope thereof, it is to beunderstood that I do not limit myself to the specific embodimentsthereof except as defined in the appended claims.

We claim:

1. Apparatus for folding flexible sheet material comprising a pair ofpanels each having a retaining surface forming a folding board having alongitudinal axis, said panels being movable to an open substantiallyplanar position wherein said folding board forms a substantially planarsurface for the receipt of the mentioned sheet material in lengthwiseplanar disposition on the folding board and said panels being spacedapart lengthwise of the folding board to define a gap for forming atransverse fold line in the material on the said surfaces when thepanels are in folded relation, means pivotally supporting each of saidpanels in the said spaced apart relation for rotation between a positionin which the panels are disposed in the substantially planar openrelation to the position in which the panels are in a folded relation,and cooperable vacuum chamber and vacuum-port means carried by eachpanel, said vacuum-port means of each panel opening to the surface ofthe said panel, and being arranged to retain sheet material in registryon the panels under the influence of vacuum pressure.

2. Apparatus for folding flexible sheet material as claimed in claim 1and in which the means pivotally supporting the panels includesconcentric shaft means defining a common pivot axis for the panels, ahollow arm supporting each panel, and said pivot axis lyingsubstantially centrally of said folding board extending transversely tothe folding board, and the said shaft means including tubular shaftmeans which communicate each hollow arm with a said vacuum chamber andvacuum-port means so that vacuum pressure may be applied through saidtubular shaft means and a said hollow arm to said vacuum-port means.

3. Apparatus for folding flexible sheet material according to claim 1 inwhich the panels each have a generally triangular surface configurationhaving edges tapering from a relatively wide rearward end to a narrowforward end terminating at said gap.

4. Apparatus for folding flexible sheet material according to claim 3 inwhich tucking means are provided on each edge of the panels bridging thegap between the panels for tucking the edges of material projectingbeyond the surfaces of the panels of the of the folding board inwardlyand beneath the folding board to provide in the material lines of foldextending transversely of the sheet material and angularly to the saidtransverse fold line.

5. In diaper folding apparatus first means for feeding a diaper in open,planar condition, a folding board of greater length than widthpositioned to receive the diaper from said first means, said foldingboard comprising a pair of panels spaced apart lengthwise of the foldingboard to define a gap across which a diaper on said folding boardextends longitudinally of the diaper, said panels each havingsubstantially planar surfaces and tapering edges extending from arelatively wide rearward panel end to a relatively narrow forward endterminating at said gap, vacuum chamber and vacuum-port means forproviding a vacuum pressure at the planar surfaces carried on therearward end of each panel whereby, upon vacuum application, a saiddiaper may be retained on said panels, shaft means defining a commonpivot axis for the said panels adapted for rotating the panels betweenthe position in which the panels are disposed in open planar conditionto a position in which the panels are in afolded closed condition, saidshaft means including inner and outer concentric rotatable shafts, theinner of which shafts is tubular, and pairs of support arms extendingfrom the said shaft means, one of said pairs being connected with one ofsaid panels in supporting relation to the panels, and one of each pairof support arms which extends to a panel being tubular and communicatingthe vacuum chamber of that panel with the inner concentric tubular shaftmeans, means controlling the application of vacuum pressure to saidvacuum chambers and vacuum ports, and means arranged to extend acrossthe gap between panels for grasping and removing a diaper from saidfolding board in the folded position of the diaper when vacuum pressureis not applied to the vacuum ports and vacuum chambers.

6. In diaper folding apparatus as claimed in claim 5 in which hingedwing fold means lie along the opposite edges of the said panels bridgingthe gap between panels and area adapted to extend inwardly beneath paneledges to fold a diaper on said folding board to provide a generallytriangular shaped folded diaper on said panels, and pusher means carriedon the under side of each of said panels movable from a rearwardposition on the panels to a forward position beyond the said panelnarrowed ends to urge a diaper from the folding board.

7. In diaper folding apparatus as claimed in claim 6 wherein saidapparatus includes finger means supported for movement into the gapbetween the panels as the panels are rotated from the said open planarcondition to a said folded condition, said finger means comprisingtubular means for directing an air flow to the sheet material beingfolded.

8. In diaper folding apparatus as claimed in claim 5 a hinged wing foldmeans lying along the opposite edges of said panels bridging the gapbetween panels for the folding of material on said panels inwardlybeneath the panels as the panels move to the folded position and pivotmeans connecting said arm means and said wing fold means for movement ofsaid wing fold means relative to said arm means and relative to thepanels carried on the arm means.

1. ApparatUs for folding flexible sheet material comprising a pair ofpanels each having a retaining surface forming a folding board having alongitudinal axis, said panels being movable to an open substantiallyplanar position wherein said folding board forms a substantially planarsurface for the receipt of the mentioned sheet material in lengthwiseplanar disposition on the folding board and said panels being spacedapart lengthwise of the folding board to define a gap for forming atransverse fold line in the material on the said surfaces when thepanels are in folded relation, means pivotally supporting each of saidpanels in the said spaced apart relation for rotation between a positionin which the panels are disposed in the substantially planar openrelation to the position in which the panels are in a folded relation,and cooperable vacuum chamber and vacuum-port means carried by eachpanel, said vacuum-port means of each panel opening to the surface ofthe said panel, and being arranged to retain sheet material in registryon the panels under the influence of vacuum pressure.
 2. Apparatus forfolding flexible sheet material as claimed in claim 1 and in which themeans pivotally supporting the panels includes concentric shaft meansdefining a common pivot axis for the panels, a hollow arm supportingeach panel, and said pivot axis lying substantially centrally of saidfolding board extending transversely to the folding board, and the saidshaft means including tubular shaft means which communicate each hollowarm with a said vacuum chamber and vacuum-port means so that vacuumpressure may be applied through said tubular shaft means and a saidhollow arm to said vacuum-port means.
 3. Apparatus for folding flexiblesheet material according to claim 1 in which the panels each have agenerally triangular surface configuration having edges tapering from arelatively wide rearward end to a narrow forward end terminating at saidgap.
 4. Apparatus for folding flexible sheet material according to claim3 in which tucking means are provided on each edge of the panelsbridging the gap between the panels for tucking the edges of materialprojecting beyond the surfaces of the panels of the of the folding boardinwardly and beneath the folding board to provide in the material linesof fold extending transversely of the sheet material and angularly tothe said transverse fold line.
 5. In diaper folding apparatus firstmeans for feeding a diaper in open, planar condition, a folding board ofgreater length than width positioned to receive the diaper from saidfirst means, said folding board comprising a pair of panels spaced apartlengthwise of the folding board to define a gap across which a diaper onsaid folding board extends longitudinally of the diaper, said panelseach having substantially planar surfaces and tapering edges extendingfrom a relatively wide rearward panel end to a relatively narrow forwardend terminating at said gap, vacuum chamber and vacuum-port means forproviding a vacuum pressure at the planar surfaces carried on therearward end of each panel whereby, upon vacuum application, a saiddiaper may be retained on said panels, shaft means defining a commonpivot axis for the said panels adapted for rotating the panels betweenthe position in which the panels are disposed in open planar conditionto a position in which the panels are in a folded closed condition, saidshaft means including inner and outer concentric rotatable shafts, theinner of which shafts is tubular, and pairs of support arms extendingfrom the said shaft means, one of said pairs being connected with one ofsaid panels in supporting relation to the panels, and one of each pairof support arms which extends to a panel being tubular and communicatingthe vacuum chamber of that panel with the inner concentric tubular shaftmeans, means controlling the application of vacuum pressure to saidvacuum chambers and vacuum ports, and means arranged to extend acrossthe gap between panels for graspiNg and removing a diaper from saidfolding board in the folded position of the diaper when vacuum pressureis not applied to the vacuum ports and vacuum chambers.
 6. In diaperfolding apparatus as claimed in claim 5 in which hinged wing fold meanslie along the opposite edges of the said panels bridging the gap betweenpanels and area adapted to extend inwardly beneath panel edges to fold adiaper on said folding board to provide a generally triangular shapedfolded diaper on said panels, and pusher means carried on the under sideof each of said panels movable from a rearward position on the panels toa forward position beyond the said panel narrowed ends to urge a diaperfrom the folding board.
 7. In diaper folding apparatus as claimed inclaim 6 wherein said apparatus includes finger means supported formovement into the gap between the panels as the panels are rotated fromthe said open planar condition to a said folded condition, said fingermeans comprising tubular means for directing an air flow to the sheetmaterial being folded.
 8. In diaper folding apparatus as claimed inclaim 5 a hinged wing fold means lying along the opposite edges of saidpanels bridging the gap between panels for the folding of material onsaid panels inwardly beneath the panels as the panels move to the foldedposition and pivot means connecting said arm means and said wing foldmeans for movement of said wing fold means relative to said arm meansand relative to the panels carried on the arm means.